diff --git a/isisd/isis_spf.c b/isisd/isis_spf.c
index 07b855b..1cb5113 100644
--- a/isisd/isis_spf.c
+++ b/isisd/isis_spf.c
@@ -365,7 +365,7 @@
       area->spftree[1] = NULL;
     }
 #ifdef HAVE_IPV6
-    if (area->spftree[1] != NULL)
+    if (area->spftree6[1] != NULL)
     {
       isis_spftree_del (area->spftree6[1]);
       area->spftree6[1] = NULL;